<p>Large-diameter empty-hole cut blasting under in-situ stress conditions represents a critical yet challenging process in vertical crater retreat (VCR) mining. However, the influence of in-situ stress on the blasting performance of the first blasthole has received limited attention. In this study, a series of physical model tests on the first blasthole were conducted under different confining pressure combinations, and the morphological characteristics of the resulting blast craters were quantitatively investigated using 3D laser scanning reconstruction. The results indicate that the empty-hole effect promotes the formation of through-going fractures, whereas static stress suppresses the development of random cracks while facilitating crack propagation parallel to the stress direction. The blast crater can be divided into three distinct zones: a top spalling zone, a core crushed zone, and a lateral spalling zone. The anisotropy and orientation of the static stress exert a pronounced influence on the volume and cross-sectional area of the top spalling zone. The direction of static stress significantly affects the crater depth and surface morphology, and further transforms the geometry of the core crushed zone from a V-shaped expansion into a distinct zonal pattern. Under uniaxial static stress, the blasted rock exhibits a larger mean fragment size with a more dispersed size distribution, whereas biaxial static stress results in finer and more uniformly distributed fragments. Moreover, the peak tensile strain parallel to the static stress direction decreases, while that perpendicular to the stress direction increases; both tensile and compressive strain peaks reach their minimum values under biaxial equal confining pressure.</p>